Do you mean D6 tuning, as in A-D-F#-B?
Only thing I would say is normal tenor strings will have about 10lbs more tension as a set on your tenor going up 2 semitones like this.
If the tension is too high, or you have too little sustain, you can safely use CONCERT uke strings in this tuning to compensate.
Traditionally, in the olden times, this tuning was used on a soprano, in order to get a brighter and punchier tone at this scale as well as have a bit more tension, since most C6 soprano string sets usually only have about 23-25 lbs of total string tension and as such the C string on C4 can sound tubby and boomy and have intonation issues due to having too low tension. Tuning up 2 semitones can fix the tubby and other issues.
Just check your bridge for excessive bellying and dishing, and if you see this happening with the bridge rotating forwards, you may be putting too much tension on it in this tuning, and if so, the bridge can eventually be pulled right off, most of the time also tearing out some wood from the top with it.
One needs to be MORE aware of the effects of string tension if using alternate tunings, since you may be exceeding the design limits for the build of that instrument.
FYI, in standard tunings most:
- soprano string sets are at about 23-25 lbs total tension
- concert string sets are at about 30-32 lbs total tension
- tenor string sets are at 35-43 lbs total tension
- baritone string sets 48-54 lbs total tension